Optimised Method for Short-Chain Fatty Acid Profiling of Bovine Milk and Serum

Short-chain fatty acids (SCFA, C2-C5) in milk and serum are derived from rumen bacterial fermentation and, thus, have the potential to be used as biomarkers for the health status of dairy cows. Currently, there is no comprehensive and validated method that can be used to analyse all SCFAs in both bovine serum and milk. This paper reports an optimised protocol, combining 3-nitrophenylhydrazine (3-NPH) derivatisation and liquid chromatography-mass spectrometry (LC-MS) analysis for quantification of SCFA and β-hydroxybutyric acid (BHBA) in both bovine milk and bovine serum. This method is sensitive (limit of detection (LOD) ≤ 0.1 µmol/L of bovine milk and serum), accurate (recovery 84–115% for most analytes) and reproducible (relative standard deviation (RSD) for repeated analyses below 7% for most measurements) with a short sample preparation step. The application of this method to samples collected from a small cohort of animals allowed us to reveal a large variation in SCFA concentration between serum and milk and across different animals as well as the strong correlation of some SCFAs between milk and serum samples.

Towards operational multi-GNSS tropospheric products at GFZ Potsdam

The assimilation of global navigation satellite system (GNSS) data has been proven to have a positive impact on weather forecasts. However, the impact is limited due to the fact that solely the zenith total delays (ZTDs) or integrated water vapor (IWV) derived from the GPS satellite constellation are utilized. Assimilation of more advanced products, such as slant total delays (STDs), from several satellite systems may lead to improved forecasts. This study shows a preparation step for the assimilation, i.e., the analysis of the multi-GNSS tropospheric advanced parameters: ZTDs, tropospheric gradients and STDs. Three solutions are taken into consideration: GPS-only, GPS–GLONASS (GR) and GPS–GLONASS–Galileo (GRE). The GNSS estimates are calculated using the operational EPOS.P8 software developed at GFZ. The ZTDs retrieved with this software are currently being operationally assimilated by weather services, while the STDs and tropospheric gradients are being tested for this purpose. The obtained parameters are compared with the European Centre for Medium-Range Weather Forecasts (ECMWF) ERA5 reanalysis. The results show that all three GNSS solutions show similar level of agreement with the ERA5 model. For ZTDs, the agreement with ERA5 results in biases of approx. 2 mm and standard deviations (SDs) of 8.5 mm. The statistics are slightly better for the GRE solution compared to the other solutions. For tropospheric gradients, the biases are negligible, and SDs are equal to approx. 0.4 mm. The statistics are almost identical for all three GNSS solutions. For STDs, the agreement from all three solutions is very similar; however it is slightly better for GPS only. The average bias with respect to ERA5 equals approx. 4 mm, with SDs of approx. 26 mm. The biases are only slightly reduced for the Galileo-only estimates from the GRE solution. This study shows that all systems provide data of comparable quality. However, the advantage of combining several GNSS systems in the operational data assimilation is the geometry improvement by adding more observations, especially for low elevation and azimuth angles.

Assessment of Globularity of Protein Structures via Minimum Volume Ellipsoids and Voxel-Based Atom Representation

A computer algorithm for assessment of globularity of protein structures is presented. By enclosing the input protein in a minimum volume ellipsoid (MVEE) and calculating a profile measuring how voxelized space within this shape (cubes on a uniform grid) is occupied by atoms, it is possible to estimate how well the molecule resembles a globule. For any protein to satisfy the proposed globularity criterion, its ellipsoid profile (EP) should first confirm that atoms adequately fill the ellipsoid’s center. This property should then propagate towards the surface of the ellipsoid, although with diminishing importance. It is not required to compute the molecular surface. Globular status (full or partial) is assigned to proteins with values of their ellipsoid profiles, called here the ellipsoid indexes (EI), above certain levels. Due to structural outliers which may considerably distort the measurements, a companion method for their detection and reduction of their influence is also introduced. It is based on kernel density estimation and is shown to work well as an optional input preparation step for MVEE. Finally, the complete workflow is applied to over two thousand representatives of SCOP 2.08 domain superfamilies, surveying the landscape of tertiary structure of proteins from the Protein Data Bank.

Evaluation and Optimization of a Newly Developed Chemical for Sand Consolidation: HTHP Gas Wells

Sand production is a common problem in wells completed in unconsolidated or poorly consolidated formation. Several problems are associated with sand production including erosion damage, and plugging of the well and surface production equipment, such as lines, valves, etc. Various mechanical solutions have been implemented to control or eliminate sand production. Screenless completion is an alternative method to conventional sand control techniques. Screenless completion methodology involves sand consolidation, a field-proven technique which offers viable and effective strategies to prevent sand production throughout the life of the well. Sand production can lead to production loss through sand filling up, production tubing restrictions, etc. Consequently, the need for an effective sand control is mandatory. Sand consolidation is a promising technique due to significant advancement in chemicals development for sand control. The challenge with the chemical consolidation systems is their ability to provide the highest possible compressive strength with minimum permeability reduction. A newly developed sand consolidation system was assessed in this study for its effectiveness in both sand consolidation and retained permeability. Two techniques were investigated in preparation/conditioning of sand samples. Following the conditioning state, the sand samples were treated with equivalent amounts of the two components of the newly developed sand consolidation system (Resin-A and Resin-B). A consolidation chamber was used to cure sand under simulated downhole conditions of a temperature (300°F) and a stress of 3,000 psi. The consolidated sand sample prepared using 3 wt% KCl brine preflush was associated with a reduction in plug permeability of more than 99% with a compressive strength of 1,100 psi. In the second method, which employed a diesel preflush in the sand sample preparation step, an average permeability of 63 mD and unconfined compressive strength nearly 900 psi were obtained. The effect of temperature and flow rate on return permeability were investigate. The paper presents in detail the lab work conducted to evaluate/optimize a newly developed chemical system for sand consolidation in HT/HP gas wells.

The impact of surfactants on nanosphere zinc phosphate synthesis

Recently, biomaterials have attracted widespread concern because of their compatibilities with live bodies. Among advanced biomaterials, zinc phosphate nanospheres particles are potential candidates for delivering drug and dental restorations. However, their fabrication methods are complicated and non-eco-friendly. In this study, we report the impact of surfactant supplements on the wet chemical preparation of zinc phosphate. Experimentally, Di-propylene glycol (DPG) and Trimethylolpropane (TMP) were added to the solution in the preparation step to compare the morphology of synthesized particles with the non-surfactant process. The morphology was examined by transmission electron microscopy. The addition of surfactants changed particle shape to spherical with a diameter of less than 200 nm. Moreover, the synthesized particles with DPG had a solid form, while those with TMP had a hollow structure (a diameter of 50-70 nm and shell thickness of 5-7 nm). Furthermore, X-ray diffraction, Fourier transforms infrared, and Thermogravimetric analyses analyzed properties of hollow particles.

The Space of Intimacy as The Most Important Islamic Cultural Value in Traditional Iranian Architecture

This study aims to carry out a critical reading of individual spaces of traditional Iranian houses. Through recourse to expert opinion, seven traditional houses in Iran have been chosen. A deductive content analysis is used to assess space syntaxes by way of three steps: preparation, organization, and the final report. In the preparation step, the individual and family territory in Iranian culture is defined. In the organization phase, territories are classified by reviewing plans, maps, and making visual observations. Finally, conclusions are reached on the situation of privacy and individuality in the houses. It is suggested that family privacy is the main function of traditional Iranian houses. Despite the fact that spaces could be used as personal and individual territories, in practice this is not so, and individualism and individual values have been forgotten. Individuality is not considered as valuable in the sense of one who needs his/her own territory; rather, this is determined in relation with other people. Keywords: Mahram Territories, Personal Spaces, Space Syntax, Territoriality, Traditional Iranian House

WORKSHOP DAN SOSIALISASI PENGGUNAAN ALAT PRAKTIKUM IPA SEKOLAH DASAR DI SDN PULO PANJANG

Science learning in elementary schools should more emphasis on process through practicum activities, currently science learning in the class is still limited to delivering theory and rarely invites students to do practicals because of the limitations of practicum tools owned by the school. Based on observations, this is also experienced by science teachers at SDN Pulo Panjang. Based on these problems, community service activities were carried out in the form of workshops and socialization of use science practicum tools, this activity consisted of two steps, e.g. preparation and implementation. At preparation step, simple practicum tools are produced for science practicum, then these practicum tools are demonstrated at implementation step. At implementation step, the speaker explained and demonstrated several practicums related to electricity & magnetism and pressure materials. There are several things that participants gained after holding this workshop, e.g. 1) Knowledge, after the workshop it was seen that participants got new knowledge about implementation of elementary science practicum, 2) Skill, participants seemed to have tskills to carry out elementary science practicum activities, and 3) Products, after the workshop, science practicum tools will be given to the school, science practicum tools provided are equipped with guides/modules

Ultrasonic Shaking of Glauconite Pellets with Diverse Reagents for a Comparison of Their K–Ar with Already Published Rb–Sr Results

A combined ultrasonic treatment, with de-ionized H2O, dilute HAc or dilute HCl, of three Mid-Miocene glauconite samples was applied to K–Ar date the different separates in order to compare the results with those obtained by the Rb–Sr method using the same three samples and that were analyzed strictly in the same way. Two aliquots yield opposite elemental and K–Ar trends, which suggests different initial mineral compositions for the various pellets. The K–Ar data of two untreated and leached L7 and L8 aliquots are almost within analytical uncertainty from 17.3 ± 0.6 Ma to 19.6 ± 0.7 Ma (2σ), while those of the third L10 sample are slightly higher at 22.1 ± 1.2 Ma (2σ). Comparatively, the earlier published Rb–Sr ages of the three untreated samples and of the leached aliquots gave similar data for the L7 aliquots by an isochron at 18.1 ± 3.1 (2σ) Ma and for the sample L8 by an isochron with an age of 19.6 ± 1.8 (2σ) Ma, while the untreated L10 aliquot yields a very high Rb–Sr date of 42.1 ± 1.6 (2σ) Ma. This untreated L10 glauconite fraction contains blödite, a Sr-rich carbonate that impacted the two isotopic systems differently. Generally, dilute HCl or HAc acids dissolve carbonates, sulfates, sulfites and oxides, while they do not affect the clay-type crystals such as glauconites. These soluble minerals can be identified indirectly, as here, by X-ray diffraction and the amounts of leached Na2O, CaO and Fe2O3 contents. Together with the leaching of some metallic trace elements, those of NaO confirm the leaching of metals and of blödite that are both hosted by the glauconite pellets. The occurrence of this Sr-enriched mineral explains the age differences of the non-treated aliquots and suggests a systematic leaching of any glauconite separate before isotope determination and, possibly, a comparison of the Rb–Sr and K–Ar results. Ultrasonic shaking appears appropriate for physical disaggregation of any contaminating grains that may remain hosted within the pellets, even after a preliminary H2O wash, which may dissolve and remove the soluble minerals but not the H2O-insoluble silicates. The K–Ar study completed here as a complement to a previous Rb–Sr study highlights, again, the importance of the preparation step in isotopic studies of glauconite-type and, by extension, of any clay material, as all occurring minerals can interfere in the final age determinations and, therefore, differently in the mineral assemblages. All those not in isotopic equilibrium need to be removed before analysis, including the soluble Sr or alkali-enriched ones.

Modern Sample Preparation Techniques: A Brief Introduction

Due to fast growth in microprocessors, analytical instrumentations in spectroscopy, chromatography, microscopy, sensors and microdevices have been subjected to significant developments. Despite these advances, a sample preparation step is indispensable before instrumental analysis. Main reasons are low sensitivity of the instruments, matrix interferences and incompatibility of the sample with the analytical device. Most of the time spent and most of the errors occurring during a chemical analysis is on sample preparation step. As a result, any improvements in this essential process will have a significant effect on shortening the analysis time and its precision and accuracy and lowering the cost. This introductory chapter intends to draw the readers’ attention to the importance of sample preparation, the procedures of sampling and the source of errors that occur in the course of sampling. The chapter then continues with a heading on sample preparation techniques, including exhaustive and non-exhaustive methods of extraction. Microwave, sonication and membrane-based extraction techniques are more emphasized as exhaustive methods and under a new title, miniaturized methods are discussed. Automation, on-line compatibility and simplification is an important aspect of any sample preparation and extraction which is discussed at the end of this chapter.

Towards operational multi-GNSS tropospheric products at GFZ Potsdam

The assimilation of Global Navigation Satellite Systems (GNSS) data has been proven to have a positive impact on the weather forecasts. However, the impact is limited due to the fact that solely the Zenith Total Delays (ZTD) or Integrated Water Vapor (IWV) derived from the GPS satellite constellation are utilized. Assimilation of more advanced products, such as Slant Total Delays (STDs) from more satellite systems may lead to improved forecasts. This study shows a preparation step for the assimilation, i.e. the analysis of the multi-GNSS tropospheric advanced parameters: ZTDs, tropospheric gradients and STDs. Three solutions are taken into consideration: GPS-only, GPS/GLONASS (GR) and GPS/GLONASS/Galileo (GRE). The parameters are compared with two global Numerical Weather Models (NWM): European Centre for Medium Weather Forecast (ECMWF) ERA5 reanalysis and a forecast model ICON run by the German Weather Service. The results show that for ZTDs and horizontal gradients, all three GNSS solutions show similar level of agreement with the NWM data. For ZTDs, the agreement is better for the ERA5 model with biases of approx. 1.5 mm and standard deviations (SDs) of 7.7 mm than for ICON with biases of 3.2 mm and SDs of 10 mm. For tropospheric gradients, the agreement with both NWMs is very similar: the biases are negligible and SDs equal to approx. 0.4 mm. For the STDs, the GPS-only solution has an average bias w.r.t. ERA5 of 4.2 mm with SDs of 25.2 mm. The statistics are very slightly reduced for the GRE solution and further reduced to a bias of 3.5 mm with SDs of 24.5 mm for the Galileo-only observations. This study shows that all systems are of comparable quality. However, the advantage of combining more GNSS systems in the operational data assimilation is the geometry improvement by adding more observations, especially for low elevation angles.